DRV8711: need help for Decay Mode Setting Optimization

Hi user4946283,

We will investigate and reply soon.

While waiting have you looked at www.ti.com/.../slva637.pdf for suggestions?

Hi Rick

I had read the pdf before,

As a beginner,I do not know why cause this situation

according the pdf ,I had reduced TBLNK and TOFF  ,and the decay mode I had tried slow+mix and all mixed,but it is not work

look forward to your reply

thanks

Hi user4946283,

Assuming you want 5.5A in your motor, please try the following settings to start and provide current waveforms:


CTRL Register 0x0da1 --10x gain, external stall detection, 1/32 step, enable outputs
TORQUE Register 0x11ff -- 100us BEMF sample, maximum torque
OFF Register 0x2028 -- internal indexer, 20us off time
BLANK Register 0x3100 -- adaptive blanking, 1us blanking time
DECAY Register 0x430A -- use mixed decay at all times, tdecay of 5us
STALL Register 0x5040 -- BEMF/32, Stall on first step, default stall setting
DRIVE Register 0x6a59 -- defaults

The 5.5A is based on the torque register setting of FF, gain of 10, and a 0.05 Ohm sense resistor. If you desire less current, please adjust the setting.

When providing the current waveform, please add the step input.